Shoe last



Dec. 1, 1936. G CLARK 2,062,557

SHOE LAS T Filed March 26, 1935 F/GJ 1N VEN TOR.

ff new a CZ/l/PK ATTORNEY.

Patented Dec. 1, 1936 UNITED STATES PATENT OFFICE SHOE LAST George 0. Clark, Beverly Hills, Calif.

Application March 26, 1935, Serial'No. 13,135

10 Claims. (01. 12136) The invention relates to shoe lasts, and particularly to hollow shoe lasts cast from a light weight metal, such as an aluminum alloy, magnesium or magnesium alloy.

5 Metal shoe lasts for use in the manufacture of leather footwear are required to be hollow and to be cast from light-weight metal, such as an aluminum alloy, in order to hold the cost and weight thereof within practical limits. The alu- -10 minum alloys found to be most practical in this regard, however, are comparatively soft. Therefore, and particularly with respect to lasts used in the manufacture of shoes whose soles and/or heels are nailed and wherein the nails are driven 15 against the last by a nailing machine to turn the ends of the nails and clinch the same to the leather, these hollow metal shoe lasts require, as does a conventional wood shoe last, the application of a steel or other hard metal plate or portion to the base or bottom thereof to turn the nails and prevent breakage, piercing and nick-' ing of the shoe last. Heretofore it has been the practice in the shoe last art to apply to the base or bottom of the last a bent metal plate securely held to place by a number of screws. This is rendered quite difficult and expensive in view of the large number of sizes and shapes of plates, each having a different curved contour, which must be stocked by the shoe last manufac- 30 turer to accommodate all the sizes and shapes of lasts which he manufactures; and also by the labor necessary to apply the large numbers of screws required to hold the plate securely to the last. The application of such plates to metal 3; shoe lasts is even more difficult and expensive than the application thereof to wood shoe lasts due to the necessity of boring and tapping holes for the reception of the securing screws prior to the operation of applying the plates. Still .40 another consideration in the manufacture of these hollow soft metal shoe lasts to be used in conjunction with nailing machines is the reinforcing thereof to successfully sustain the great crushing stresses applied thereto by the nailing -3 machines, the soft metal of which they are made naturally rendering them structurally Weak in themselves.

It is therefore the primary object of this invention to provide a shoe last having a sprayed layer of hard metal applied to the base thereof.

A further object is to provide a shoe last having a rough bottom surface on which a leather insole may be laid with minimum likelihood of slippage thereon.

A further object is to provide a shoe last with a hard metal base layer of minimum thickness for its purpose, whereby the total weight of the shoe last is maintained at a minimum. 60 A further object is to provide a shoe last with a hard metal base layer which may be applied thereto at minimum expense.

A further object is to provide a hollow metal shoe last with a novel heel construction includ. ing combined reinforcing and last mounting 5 means.

A further object is to provide the heel portion of a hollow metal shoe last with a hard metal sleeve for engaging the work holder of a shoe making machine, said sleeve spanning the in terior cavity of said heel portion and being imbedded in the metal of opposite Walls thereof at its ends whereby the shoe last is supported at the wall thereof to which the stresses exerted I by the nailing machine are applied.

With the above and otherobjects in view, the invention resides in the combination and arrangement of parts as hereinafter set forth, and shown in the drawing, it being understood that changes in the precise embodiment of the invention may be made without departing from the spirit of the invention.

In the drawing:

Figure l. is a longitudinal vertical sectional view of the shoe last taken on line i-l of Figure 2.

Figure 2 is a bottom plan view of the shoe last.

Figure 3 is an enlarged fragmentary sectional view of the base of the shoe last taken on line i--l of Figure 2.

Referring to the drawing, which illustrates the preferred embodiment of the invention as applied to a hollow aluminum jointed shoe last of type illustrated in my copending application now Patent No. 1,994,569, granted March 19, 1935, the numeral l6 designates the toe part and the nu- 3 meral H the heel part of the last. Each of these last parts includes a base or bottom wall l2 and a joint wall l3. The joint walls of the. toe and heel parts of the last are provided with complementary interfitting joint knuckles l4 and recesses 5 for the reception of the knuckles. A pin l5 passes through the knuckles M to pivotally interconnect the last parts it and l 5. Suitable quick-throw'means is associated with the hinge joint; and, as illustrated, comprises a projecting cam-forming hard metal ball ll imbedded in a knuckle M of the toe part, and a second hard metal ball 3 pressed against ball H by a spring l9, said ball 18 and spring I9 being mounted in a pocket 38) extending interiorly of heel H of the last and opening into the recess l5 in which toe part knuckle which carries ball ll fits.

In the heel portion ll of the last is imbedded an open-ended hard metal sleeve 2| having a circumferential enlargement 22 adjacent its open 5 end and a longitudinal extension 23 of reduced dimension at its opposite end. The bottom wall l2 of the heel part is provided with an integral interior enlargement 24 which bears upon the inner end of sleeve 2| and in which extension 23 of said sleeve is imbedded. The other end of the sleeve passes through the top wall of the last with its open end preferably terminating flush therewith. The imbedding of enlargement 22 and extension 23 serve to lock the sleeve in desired position in the heel part of the last. The sleeve 2| is adapted to fit over the stud or other work holder of the shoe making machine, and its imbedded end-mounting and its spanning relation to the heel member serve to reinforce the weak hollow heel part to enable it to withstand the crushing stresses applied thereto in the performance of the nailing operation on the shoe. Likewise, it will be seen that the end of sleeve 2| bears directly upon base wall l2 of the heel part to which the stresses incident to nailing are applied, so that the construction provides for the direct support of the shoe last at the part or wall thereof at which stress is applied and minimizes stresses applied to the remaining walls of the last.

To the bottom or outer face of the base l2 of the toe and heel parts of the shoe last is applied a thin layer 25 of a hard metal, such as iron or steel, whose thickness is just sufiicient to enable it to withstand the stresses applied thereto in the nailing operation, The thickness is carefully maintained at this low limit to avoid unnecessary weight, and to keep the total weight of the shoe last as near to the weight of a wood shoe last as practical. The hard metal layer 25 is sprayed on the bottom of the shoe last, so that the thickness and strength of the sprayed layer is readily controllable and may easily be obtained at minimum operative limits. The sprayed layer of the hard metal firmly adheres to the aluminum wall H. of the last, as by flow thereof into minute surface indents or irregularities in the aluminum wall l2, which may be provided by a sand blast or other suitable means; and the adherence is also caused by the production of a certain degree of fusing of the aluminum by the heat of the sprayed metal, so that the bond between the aluminum and the sprayed layer of hard metal will not be broken by the driving of nails thereagainst. The sprayed metal layer 25 is provided with a rough outer surface, as best illustrated in enlarged View in Figure 3, and this surface facilitates turning of the points of the nails as they are driven thereagainst, and also retards slipping of leather insoles placed thereon in the shoe making process.

While the invention has: been described and i1- lustrated with particular reference to the provision of the sprayed hard metal layer to a hollow soft metal shoe last, it is not limited strictly thereto, inasmuch as the invention contemplates the provision of a sprayed layer of hard metal to the bottom face of a shoe last formed of any material, whether metal, wood or other material, to closely adhere thereto and to provide a layer of sufiicient strength and hardness to resist and turn nails driven thereagainst in the shoe making operation.

The invention having been set forth What is claimed as new and useful is:

1. A shoe last having a sprayed layer of hard metal of sufficient thickness thereon to provide a surface against which nails may be driven and deflected.

2. A shoe last comprising a body portion of light weight having a sprayed layer of hard metal of sufficient thickness firmly adhering thereto to provide a rough surface against which nails may be driven and deflected.

3. A shoe last comprising a body portion of magnesium alloy having a sprayed layer of harder metal thereon of sufficient thickness to provide a surface against which nails may be driven and deflected, the individual particles of which are fused to each other and to the body portion and present an outer sprayed surface.

4. A shoe last comprising ,a body portion of aluminum alloy having a sprayed layer of harder metal thereon of sufficient thickness to provide a surface against which nails may be driven and deflected, the individual particles of which are fused in sprayed impingement upon each other and upon the base forming an integral structure therewith.

5. A shoe last including a hollow heel portion having a base wall to which pressure is applied, and a hard metal sleeve adapted for engagement with a work holder embedded in said heel portion to span the interior cavity thereof, the inner end of said sleeve abutting said base wall whereby said last is supported at the portion thereof to which pressure is applied.

6. A shoe last including a hollow heel portion having a base wall, and a hard metal sleeve having an extension of reduced dimension at one end thereof providing a shoulder, said sleeve being imbedded in said heel portion to span the interior cavity of said heel portion with said extension imbedded in said base wall and said shoulder bearing on said base wall.

'7. A shoe last including a hollow heel portion having opposed walls, and a hard metal sleeve having an enlargement at one end and an extension providing a shoulder at the other end thereof, said sleeve spanning the interior cavity of said heel portion with said enlargement imbedded in one wall and said extension imbedded in and said shoulder bearing against the other wall of said heel portion.

8. A shoe last including a hollow heel portion having a base wall provided with an interior enlargement, and a hard metal sleeve having an extension of reduced dimension at one end thereof providing a shoulder, said sleeve spanning the interior cavity of said heel portion and imbedded at its opposite ends, the extension of said sleeve being imbedded in the enlargement of said base wall with said shoulder bearing on said enlargement.

9. A shoe last comprising a body portion formed of light weight metal having'a contoured base covered with a sprayed layer of hard metal, the individual particles of which are fused in flattened sprayed impingement upon each other an upon the base.

10. A shoe last including a hollow heel portion having a base wall to which pressure is applied, and a steel member adapted for engagement with a work holder, embedded in said heel portion to span the interior cavity thereof, the inner end of said member abutting said base wall whereby said last is supported at the portion thereof to which pressure is applied.

GEORGE C. CLARK. 

